Slide Editor | Slides, Layouts & Notes

Home ▸ Slides carries five commands: New slide, Duplicate, Delete, Earlier and Later. All five are undoable, and all of them are on the shared SlideEditorController for a host that builds its own chrome.

var c = editorView.Controller!;

c.NewSlide();            // after the current slide, and opens it
c.DuplicateSlide();      // the copy goes straight after the original
c.DeleteSlide();         // never asks — the view does
c.MoveSlideEarlier();    // or MoveSlideLater(), or MoveSlide(from, to)

c.CanDeleteSlide;
c.CanMoveSlideEarlier;
c.CanMoveSlideLater;

New slide

A new slide takes the current slide’s layout — a deck is built slide after slide of the same kind — except after a title slide, where it takes the master’s Title and Content layout instead. That is PowerPoint’s rule too. Ctrl+M adds one on Blazor.

It arrives with the layout’s placeholders, empty. Each shows its prompt — Click to add title, Click to add text — inside a dashed outline, laid out in the placeholder’s own size, font and bullet, so the prompt sits exactly where the first keystroke will. A layout that wrote its own prompt text is quoted instead.

The prompts are editing chrome, not content: the viewer and the slide show never draw them, a search never finds them, and the one the caret is inside disappears. Date, footer and slide-number placeholders are left off, the way PowerPoint leaves them off.

Duplicate

The copy’s XML is the original’s; its pictures, charts and media are shared with the original — two relationships to one part, which is how PowerPoint stores a picture pasted twice. The notes page is the exception: it points back at its slide, so the copy gets a notes page of its own. Editing the copy never changes the original.

Delete asks first

Both toolbars confirm before deleting, with Cancel focused so an Enter that lands on the dialog is the harmless answer:

Delete slide 3? “Roadmap” and everything on it will be removed from the deck. You can undo this.

Turn it off with ConfirmSlideDelete="false", or put the app’s own dialog in its place — the callback gets the index of the slide about to go and returns whether to delete it:

<SlideEditorView Deck="deck"
                 ConfirmDeleteSlide="@(i => Dialogs.Confirm("Delete slide?", $"Slide {i + 1} will be removed.", "Delete", "Cancel"))" />

slideEditorView.ConfirmDeleteSlide = i =>
    dialogs.Confirm("Delete slide?", $"Slide {i + 1} will be removed.", "Delete", "Cancel");

On MAUI the built-in confirmation is the page’s alert. With no page to show it on, nothing is deleted — a confirmation that silently never appears must not become a delete that silently always happens.

SlideEditorController.DeleteSlide itself never asks: confirmation belongs to whatever knows how to ask. If you put your own button over a bare SlideEditor, confirm before you call it — RequestDeleteSlide() (Blazor) and RequestDeleteSlideAsync() (MAUI) run the view’s own flow.

Undo brings back the same slide — even after a save

A deleted slide’s part stays in the live package, out of the running order, and is stripped from the saved copy only. Undo therefore puts back the very same slide — its pictures, its notes, its relationships — rather than a reconstruction of it, and that holds after the deck has been saved. The file on disk never carries it.

Reordering

Drag a thumbnail in the slide rail. An insertion line shows where it will land, the rail scrolls itself near either edge, and the drop is one undoable move; a small wobble is still a tap, which just opens the slide. Earlier and Later swap the current slide with its neighbour; MoveSlide(from, to) moves one anywhere, with to counted after the slide has been taken out. The editor follows the slide it moved.

Sections and custom shows

A deck with sections must list every slide in exactly one of them, in running order — PowerPoint repairs a file that does not. A new or moved slide joins the section of the slide it now follows, a deleted one leaves its section, and a custom show loses its reference to a deleted slide. Undo restores all of it exactly, including a slide moved back into the section it left.

After any change

Every structural change — an undo and a redo included — clears the shape selection and goes to the slide it happened at. A selection is an index into the slide that was showing; after a reorder it would name a shape on a different slide. SlideDeck.SlidesChanged reports each change, with the slide to go to, for a host keeping an index of its own. A viewer sharing the deck clamps its index when the slide it was showing is deleted.

The slide rail

A column of thumbnails to the left of the slide — ShowSlideRail, on by default, hidden below 600px where there is room for one column. Tap to open, drag to reorder. It follows the editor, so a slide reached by the arrows, a search or New slide scrolls into view. The behaviour is the shared SlideRailController, identical on both hosts; SlideRail is also usable on its own.

Layouts

Home ▸ Slides ▸ Layout lists the master’s layouts with the current one checked. Picking one re-lays the slide: placeholders match the new layout’s by index, then type, and take its position; one with content and nowhere to go is pinned where it was drawn; an empty one without a match goes; the new layout’s unmatched placeholders arrive empty, with their prompts. New slide with layout adds a slide on a chosen layout.

foreach (var layout in c.Layouts) { /* Name, Index, IsCurrent */ }
c.SetLayout(c.Layouts[1]);
c.NewSlide(c.Layouts[1]);

Speaker notes

The Notes button in the status bar (or ShowNotes) opens a notes box under the slide. It writes through as you type, and a run of edits undoes as one step. A slide with no notes page gets one, and a deck with no notes master gets one too — with a copy of the slide master’s theme — so the file still opens cleanly in PowerPoint.

c.Notes;            // the current slide's notes, or null
c.SetNotes("...");

Not implemented

• Hiding a slide from the show.